One problem related to wiring has been reported for the 2018 GMC Acadia. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2018 GMC Acadia based on all problems reported for the 2018 Acadia.
I am getting a error message "shift to park" even when the vehicle is clearly in park. It drains the battery because you can't shut off the vehicle with the message. Have to jiggle the shifter after several attempts it may clear the message. Had one time I got out with the error message and the vehicle began to roll with no one in it even though the shifting area said "p" for park. And sitting in my garage with car running could not get the shifter to move to reverse, drive, anything, had to shut it off 3 times before it would register. Have had the wiring harness already replaced.